The invention relates to an apparatus for processing viscous substances or substances which can be made viscous through processing.
In the present context, processing is understood to mean plasticizing, mixing, degassing, reacting, etc. Such an apparatus is known from DE-A No. 29 33 655 (corresponding to U.S. Ser. No. 935,257). In this case, adjacent chambers in a casing have interconnecting overflow passages which, based on the rotation direction of disks, are located in front of a fixed damming-back member projecting into the vicinity of the shaft in one chamber, so that through the damming back of the material in front of the damming-back member, said material is forced via an overflow passage into an adjacent chamber. A basic advantage of this apparatus known as a "Diskpack" is that through the damming back of the material in front of the damming-back member, there is a relative movement between the substance to be processed and the faces of the disks, so that the walls bounding the chamber act on the material therein and bring about the liquefication, plasticizing, feeding, pumping, mixing or degassing thereof. An important advantage of this known apparatus compared with other single-shaft processing means is that it is possible to achieve a much higher pressure build-up and a much better delivery efficiency. It is possible to obtain in a very simple manner large degassing surfaces. However, it is disadvantageous in this known apparatus that the fixed damming-back member is not subject to a self-cleaning action and that relatively large diameters are required with high throughputs per unit of time, which lends to considerable mechanical and process problems in the case of a throughput exceeding 10 t/h. A further very important disadvantage is that the transfer of viscous materials between the chambers must take place outside the actual process zone, which has a disadvantageous effect on the processing quality.
An apparatus which is in principle identical to that described hereinbefore is known from U.S. Pat. No. 4,142,805.
U.S. Pat. No. 3,042,264 discloses an apparatus for processing substances having a casing, in which are arranged two parallel bores which penetrate one another. Each of these bores contains a shaft with disks arranged in rotary manner thereon, a disk of the adjacent shaft projecting into the chamber bounded between the two disks arranged on a shaft. Relatively large openings are provided in the disks and through which on one side is axially conveyed the material, whilst they serve to comminute and mix the same, the boundary lines of said openings serving as shearing or cutting edges.